Pneumatic tube.



C. i", HSK,

NEUMATIC TUBE. APPucATwN man fis. e. m3.

Lla' atented A111213, 1915.

2 SHEETS-'SHEET 1.

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@16AM/wu:

Cl F. HSK.

PNEUMAUC TUBE` APPUcATsoN min m16, 1913.

Patented A131213, 1915.

2 SHEETS-SHEET 3.

therefwill be no wrinkles alon the rim side 'and no undue tension along t e tread side,

f the center of `this stri is the part that will and vtherefore' the finished article will wear muchlonger. l 1

' In' the accompanying: drawings, .Fig. 1 shows a sheet of woven fabric, and the lines across theg'same indicate h'ow` I cut a strip from the same on lthe bias; and Fig. 2 'shows the same strip after it has been Vstretched or forcibly, expanded to the extent that its meshesy are bf different shape than in Fig. 1. Fig. 3 shows a detail I may employ, and this consists in expanding the fabric strip 1 to a. little greater degree along itstransverse center'` than at either edge. As

be nearest the hub an will therefore follow the smallest vcircl'efwithin the tube, `and it should be. expanded most because it will have toexpand most' for` its mesh to resume its normal condition. However, this is a detail which may well be leftto the manufacturer. In Fig.- S'the numeral 2 designates the transverse center of this strip 1, the cen- 'ter being supposed to be expanded more than the edges.

' designates a strip which is cut straight across the fabric 4, and a strip so cut might Y be applied to the outer orl tread side of the tube. e The fabric ma be canvas, friction duck, or any material? whichis commonly employed in thisy connection. Fi'g. 5 shows one 4manner of assemblingthe vconstituent elements of this tube 'around a mandrel M,

' herein shown as a steel tube of proper circumference `to form the' bore o thepneumatic tube being made.; In forming the pneumatic tube on this'mandrel, I cut the rubber into afsheet 5 whose length corresponds with that 4of the circumference ofthe j finished article f and whose width is about gftwice the circumferenceof the tube when finished. One edge of this sheet 5 is laid on the mandrel M, preferably at a point 6 as indicated, the sheet is then carried once around the mandrel to the point Aof starting, a strip ofthe bias and expanded fabric l is then laid beneath the mandrel and a strip of let us say normal (2'. e. unstretched), fabric is laid over`- the mandrel, andthe rubber sheet 5 given a 'second wrap around the same so that it incloses the two fabric strips between its .owng two convolutions a s shown in Fig. 6, and what was its outer edge 7 at `first is here shown as standing about over its inner edge or point of starting'. The article as thus far constructed is now wrapped and cured', and then stripped from the man- -vdrel when the expanded inner side will con- "tract 'slightly so `that 'the ends of the tube can be brought together, and they are joined byfany of the well known means; and later 'Ni/hen the tube is inflated the biasexpandcd fabricfon the rim side will'contract freely back to its normal mesh and settle to fit the The numeralS-'in Fig. 4.

tire shoe'cavity without wrinkles.- It will be i noted therefore, that in the finished article the rubber and the fabric are nowhere'under undue tension when the tube is inflated. rIn fact, if the tube could be inflated without its ends being connected,'it would be found Aief thatl it would automatically assume a circu- .and may be spaced at the other side as at '9.

Bythis word spaced, I mean that the. i. edges may be left separated from each other,

so that between them there is nothing but.

thev two or more convolutions or layers of rubber, vulcanized to each other direct. Such a space I do by preference leave 4at each side of the tube, because where the fabric is inserted the tube loses its expansibility vwithout; losing its flexibility, and omlinarily it should expand at some point so that when iniiated it willfill the casing.4 The expany sion point or points I prefer tomake in the shape of a band along one sideor bands along both sides of the tube, rather than along its tread or its rim side', because the tread side is subject-to wear within thel casing as well as the rim side, `and both lneed the protection of the strip of fabric, and

In Fig. 9 the expansi therefore the sides of the tube are,` the proper which overlap the edges of the fabric strips and extend across the bands, and these rubber strips will of course be vulcanized to the rubber convolutions in makinghthe tube.

Inl Fig. 10 I have illustrated the possibility of amplifying'this method by the addi# tion of other strips of fabric, as when the tubemust be made very strong, for use for instance on motor trucks. Herein I have on bands are reinforced by rather narrow strips 4I0 of rubber illustrated an additional strip at 11 on the tread side, making two strips herein all, although' of course there could be a greater number; but in this view I have not amplified the number of'strips on the rim side,

because one thickness of fabric' will ordinarilybe sufficient at that point, although I do not Wish to be limited to the same. It isl essential, however, that the rim-side fabricstrip -shall be stretched to such an extent 'that it may be said to be expanded before being applied, so that the principal feature ofmy' invention' will result as labove explained. A tube constructed in this manner may be employed as an ordinary hose-pipe tire which' has no outer'casing. I have alsom'ade use of Fig. 10 to showthat'metallicor leather or other stripsl or platesfof armor 13 this kind, Whether it be used With a casing or Without, but of course this feature-'of armoring the' tube might be employed' `1n other Ways than as herein shown.

the tube at right angles toits aXisand'bn-. smaller scale. Herein is shown how Ic'aus'e'. the meeting ends of the various strips, to break joint With each other aronndthe' tube.

the obvious reason being because Where these ends meet the tube 1s weaker and Iu would there wehave lbe weakened points lie opposite yiiiiibrokeY it? vortions of 0 other thicknesses Lof layers o' fabric. It will hardly be necessary to give illustrations of the manner in which a tube thus made is built up, but it will be clear to those familiar with the business that the several layers of fabric on the tread side will be properly Y applied before the sheet 5 is rolled as shown in Fig. 5, or some of the layers 'could be inside the second convolution and others outside it and the convolutions themselves amplilied so that a thickertubejvould result;

and in bringing the ends of the tube together to complete the finished article, the longer end of one layer on the tread side will be inserted into the proper space for it between the convolutions of the rubber Sheet 5 at the other end, so that the break joint feature above referred to will be carried out. I have purposely omitted giving proportions of parts as they are not essential to the successful operation of my method.

Reiinements and additions may be made as will be clearly understood. Forinstance, the infiating nipple and valve Will be applied in the ordinary manner and at a proper point, but I consider it unnecessary to illustrate this feature or the tire casing.

' lVear strips l5 and 16 may be appliedalong i the outer and inner sides of the nished pneumatic tube as shown in Fig. 7 so as to prevent the saine from being -Worn by the inside of the tread of the casing or chafed or pinched along the seam at the rim side y ofthe casing; vthese strips may be applied by cementing themonto the finished tube, or they mightV be applied before vulcanizing the component parts together and in that case the strip along the rim side will by preference be cut bias and expanded in the manner above set forth.

-As above suggested, I prefer that eXpansion bands be left along one or both sides 4@of the tube, Where the material of the same 'is Wholly rubber, although this is not absolutely necessary and may be omitted in some instances. Its purpose is to permit the tube to expand along these bands rather than on the -tread or the rim side. Also I prefer side.

that the. entire. inner convolution shall be of rubber or rubber composition, so that it will be air= tight which some fabric is not. The fabric may b e treated to make it impervious to moisture, and it may be treated to resist tha/heat sometimes generated under heavy fv leadaapr high speed. Fig. 1l is a diagrammatic section through."

What is claimed as new is:

pneumatic tire tube comprising a of rubber, a strip of fabric carried by the tread portion of said rubber body, and 'astri'p of expanded bias fabric carried b 'the r'iinv portion of said body.

2'. A pneumatic tire tube comprising a "bodyvof rubber, a fabric strip carried bythe tread portion ofsiid body, a second strip of bias fabricearried by the'rirn portion of said body and expanded circumferentially, the edges of said strips being spaced at one side of the tube leavingan expansion band of rubber. l

3. A tube for pneumatic ,tires comprising an elastic body having a strip of fabric carried by the tread portion thereof, a second strip of longitudinally expanded bias fabric carried by the rim portion of the body, the

edges of said fabric strips on one side ofy the tube being spaced to leave an expansion band at said sideof the tube and a strip of rubber overlapping said spaced edges andv extending across the expansion band.

4. A pneumatic tire tube comprising a.

rubber body, and a strip of expanded fabric embedded in said body along its rim side.

\5. A vpneumatic tire tube comprising a rubber body, and a strip of expanded bias fabricy embedded in said body along its rim 6. The herein described inner tube for pneumatic tires which consists of a 4tubular rubber body, along the tread side thereof a fabric stripv of normal mesh, and along the rim side of said body 'a bias fabric strip expanded While the tube is deflated and of normal mesh when it is inflated in a casing of proper size.

7. A rubber tire tube havingy embedded along one side thereof a fabric strip eX- panded longitudinally and to a greater degrec. along 'the center of the strip than a l ong its edges. I*

8. The herein described inner t@- pneumatic tires comprising a p straight elastic rubber tubing h ends united, a strip of fabric ei its tread side and substantrl ing in length with the inte ence of the shoe or casing i the tube, a second strip yof ffl in a longitudinally stretti the rim side of the tube, `1 second fabric strip runni l rrespond- {circumferich receives .-.ic embedded condition in threads of the 'g diagonally, and

o f elastic rubber overlapping said spaced In testimon7 whereof I hzwehereunto set l edges and extending ar'oss the expansion my hand in presence of two subscribing-viti bands. nesses. Y

-9. A pneumatic tire tube comprising a CLARK FRANCIS'FISK. 5 rubber body, and a strip of bias fabric ex- Witnesses: Y

panded longitudinally and embedded in WM. C. SMITH,

said bodyulong one side thereof. A i J. HAROLD SMITH'. 

